None of the above documents teaches nor suggests the invention.
Thus, the invention provides a multilayer structure (C), comprising an extrudable central pressure-sensitive adhesive layer (3), where the central adhesive layer comprises two extrudable pressure-sensitive adhesive sub-layers, and two extrudable outer layers (2) and (4), at least one of which is able to function as a tearable welding layer (4), the structure (C) being formed by collapsing a co-extrusion bubble.
According to one embodiment, collapsing the co-extrusion bubble is done in an oxidizing medium.
According to another embodiment, the extrudable central pressure-sensitive adhesive layer (3) comprises a thermoplastic elastomer-based hot melt adhesive.
According to one embodiment, each of the extrudable outer layers (2) and (4) comprises a polyethylene.
According to another embodiment, the outer layers comprise metallocene PE.
The invention also provides a process for preparing a structure according to the invention, by collapsing the co-extrusion bubble on itself.
Collapsing is preferably done in an oxidizing medium.
The invention also provides a multilayer package comprising an extrudable inner layer interposed on one outermost side of the central pressure-sensitive layer, where the inner layer is able to function as a tearable welding layer, and where at least a portion of the package is formed by welding the inner layer to itself.
The invention also provides a process for preparing a packaging according to the invention.
The invention will now be described in more detail below, with reference to the attached drawings.